Chronic kidney disease in snake envenomed patients with acute kidney injury in Sri Lanka: a descriptive study.

BACKGROUND: Data on the long-term outcomes of acute kidney injury (AKI) in envenomed patients leading to chronic kidney disease (CKD) are scarce. The aim of the study was to investigate this issue and to determine the predictive factors in developing CKD.

METHODS: The records of a series of 54 patients who had AKI following a snakebite during the period 2004-2009 and who had been followed up were reviewed in the nephrology unit, Kandy, Sri Lanka. The primary outcome measure was the failure of renal functions to return to normal within 1 year. The renal histology was studied in seven patients.

RESULTS: The mean age of the group was 50 years (SD 13 years) and 39 (72%) patients were men. The offending snakes were Russell's viper and hump-nosed viper in 15 (28%) and 13 (24%) patients, respectively. At 1 year, 20 patients (37%) had developed CKD (CKD group) and the rest (63%) had recovered (recovered group). The acute stage serum creatinine was high in both groups with no difference (on admission, p=0.134; on discharge, p=0.323), but the CKD group showed significantly high serum creatinine at 2 months after AKI (p=0.004). Mean duration of renal replacement therapy (RRT) of the recovered group and CKD group were 7 (SD 5) and 16 (SD 12) days, respectively (p=0.015). Renal histology of six CKD patients showed predominant glomerular sclerosis and interstitial nephritis.

CONCLUSIONS: CKD is an outcome of severe AKI following snake envenoming probably predicted by the length of RRT.